apple still tops a list put out by terminix of cities with the biggest bed bug problem, followed by philadelphia at number two. and at number three, detroit, that has seen whole buildings evacuated. but a surprise, four of the top 15 are in ohio. middle america. it's all fodder for psychiatric consultations -- >> it really is both a mystery, because you can't see them very well, particularly bed bugs, and also the sense of loss of control. >> reporter: -- and for late night comics. >> you folks applauding or trying to kill bed bugs? >> by the way, the scariest thing about bed bugs, no place is safe. >> reporter: sorkin only sees a growing problem no one seems able to control. one that can be fought with pesticides, steam and frequent vacuuming. but that still leaves some people living with this, really. >> you wouldn't imagine residents have colonies as thick as this. >> yes. the person lying on the bed had all these bugs crawling on them. >> reporter: that much? >> that much. >> reporter: crawling and feeding their way across the country. mike taibbi, nbc news, new york. >>> when we come back h